Fast CU partition for H.264/AVC to HEVC transcoding based on fisher discriminant analysis

Abstract

In this paper, a fast CU partition algorithm for H.264 to HEVC transcoding based on Fisher Discriminant Analysis is proposed. Using the classification model built with the extracted features from H.264 bitstream, the CU splitting of depth 0 and 1 can be directly determined without rate distortion optimization process, and a simple mode mapping method is used to determine CU splitting in depth 2. To ensure the accuracy of classification model, an online learning strategy is designed to update the model thresholds and weight vectors in time. The experimental results show that the proposed algorithm obtains a speed-up to 1.90× on average with 2.75% BD-rate loss under the low-delay P configuration.